The blind, 17-year-old high school senior in Phoenix, Ariz., completed the trek on Sunday along with two other sightless swimmers.

"It's just good to show people I can do everything, really," Ashton told the San Francisco Chronicle after he made the 1.25-mile swim across San Francisco Bay.

Ashton has previously climbed Mount Kilimanjaro, crossed the Grand Canyon and thrown out the first pitch at a major league ball game. He was accompanied on the swim by 24-year-old Tanner Robinson, who works in state government in Arizona, and 19-year-old Katie Cuppy, a freshman at Northern Arizona University.

The three blind athletes were guided by sighted swimmers Mike and Paul Tiffany, both of Phoenix.

The challenge when swimming blind is staying on course. But Robinson said there's also an advantage "The nice thing about being blind is you don't know where the finish line is," he said. "It was just like another training."